Lead for sounding purposes



Jan. 13,1931. w. RUDOLPH ET AL LEAD FOR SOUNDING PURPOSES Filed May 25, 1928 Patented Jan. 13, 1931 UNITED STATES PATENT OFFICE WILHELM RUDOLPH AND BERNHARD SETTEGAST, 0F KIEL, GERMANY, ASSIGNORS, IBY

MESNE ASSIGNMENTS, TO ECHOMETER GESELLSCHAFT MIT BESCHRANKTER HAF- TUNG, OF KIEL, GERMANY LEAD FOR SOUNDING PURPOSES Application filed May 23, 1928, Serial No. 280,007, and in Germany June 2, 1927.

The invention relates to a sounding lead for carrying out the well-known method of sounding in which the lead is thrown out from a ship, for example, without a line attached to it and on meeting the surface to be sounded gives a signal, so that from the time of fall the depth to be sounded can'be found. The soundingleadaccording to the invention is mainly intended for soundings in water i and is therefore shaped in well-known manner in substantially stream line form. Its function is based on the electric principle, that is to say, on the impact of the lead on the bottom an electric circuit is closed which serves for producing the signal. This is appropriately effected by causing the current to detonate a primer cartridge, so that the actual signal becomes an acoustic one. Of course light signals or signals of another kind can also be produced.

The invention consists further of a series of improvements in different parts of such a sounding lead, the combination of which provide increased certainty, reliability and accuracy of the measurement. Chiefiy these improvements relate to the form of the lead body. In order to obtain soundings as exact as possible, it is desirable to obtain a drop of the body within the medium, usually water, as free as possible from disturbances. In order to shorten the sounding, the sinking speed should be made as great as possible, that is to say, the resistance to the travel of the body should be as small as possible. The body is therefore so constructed according to the invention that its greatest cross-section lies between and of its total length and towards the side which is lowermost on falling. Experience has shown that with such a distribution the greatest sinking speed can be obtained.

In order to further perfect its stream line form the part of the body directed downwards, which lies between the greatest crosssection and the leading end, is so constructed that as far as possible it represents exactly a paraboloid.

This part of the body or a portion thereof is appropriately arranged in well-known manner separable from the maln body and relatively movable with respect to it, so that on impact on the surface to be sounded it is displaced with reference to the main body. This displacement is utilised, in a manner also well-known, to produce the signal of impact. In the present example this part is directed downwards and constructed as a cap and it must, in accordance with the invention, amount at least to of the length of the whole lead. Appropriately, in accordance with the invention, the greatest cross-section of the sounding body is located on the boundary line of the cap and the main envelope of the body. In order to avoid eddies and retardations, the upper edge of the cap should be in close connection with the lower edge of the main envelope of the body; but it is better to be somewhat narrower than the edge of the envelope. Otherwise water eddies would arise in the direction of travel behind the edge of the cap, giving rise to retardation and irregularities of fall of the sounding body.

In order to prevent this movable cap from giving the sounding signal on the impact of the lead on the water, it must for this period be prevented from moving by a device which does not give the cap freedom of movement until after it has struck the water surface. According to the invention this is obtained by arranging a detent in the path of movement of the cap itself, or on constructional parts rigidly connected with it, adapted to be operated by the water pressure, which is released from the locking position at a predetermined depth of water by the pressure existing there. Preferably for this purpose a watertight air-filled capsule with flexible diaphragms is employed which is provided with a pin forming the detent and which, on deflection of the diaphragms under the influence of the water pressure, is removed from the path of the cap or the other locked mem bers. Sounding bodies of this kind may be constructed simplest as electrically operated explosive leads as already previously proposed. For this purpose there are combined an explosive charge with electric ignition, a source of current and a contact adapted to be closed on impact of the cap. An essential feature cell adapted to the explosive charge is therefore impossible in the dry condition of the lead. As soon as the lead is thrown into the water, sea water enters or the salt isdissolved in the water and the cell is ready for use. In order to avoid washing out of :the salt, the :latter isappropriately suspended in 'a :porous or fibrous body located between the electrodes. In

' order to secure luniform penetrationof the water, one of the elect-rodesior both areperforated at many places. F or the sake of simplicity, the -.envelope of .the lead can be used as-one of the two electrodes and a corresponding sheet metal cone within the same as second telectrode.

, in theelectricallyoperatedlead, the above-. mentioned pressure safety device can be constructed as electric contact device instead-of a mechanically blocking device, in such a way that by the pressure actionof the water, for example on the diaphragm-of the capsule, a locking device is not removed, but a contact located in the ignition .circuit is operated which prevents premature ignition or a short-circuit .for the ignition circuit is opened. v

In the -.drawing two-constructional examples-of the invention are represented inlongitudinal section. 1 indicates the envelope of the main body of the lead, 2 tail steering surfaces 3 the cap movable relatively to the main body. The cap'is held away from the main body in normal condition by means of a spring 5, the spring bearing against the abutment 6. The centre of the cap carries a contact pin 4, whose point makes contact with the contact spring 9 when the cap moves towards the main body. In the lower part of the main body is arranged aballast and inertia body 7, which closes the main body at the bottom and on which the essential parts of the lead are secured-and in which the upper end 8 of the contact pin is guided. The explosive charge is indicated with 10. The electric cell .is formed by the envelope 1 of the main body and a coaxial sheet metal cone ll with holes 18 for penetration of the wa-' ter. Between 1 and 11 is arranged a porous intermediate layer .12 impregnated with the salt of the electrolyte. Appropriately in well-known manner two different electrolytes aroused in orderto prevent too powerful and too rapid'polar-isation ofthe cell. In theicaseof a copper-zinc cell, copper sulphate is advantageously employed on the copper and magnesium sulphate on the zinc. Both salts preferably are separately suspended in two different porous layers lying one on top of the other.

The arrangement of the electric leads isverysimple. The .pole 11 of the cellis connected at 13 by means of a conductor with the ignition V v there a conductor 15 leads to'fthe cont-act spring-'9 and on contact between spring?) and a rapid escape of the air. The admission of the water to the'electrolyte salt is effected through the openings .18 in the inner electrode of the cell. This arrangement gives a very great security against an unintended wire 14 of the detonator. From moistening and activating of the cell by rain,

spray and the like. 7

Regarding the contact it has still to "be mentioned that ,a specially careful insulation between the contact elements 8 "and .9 is by no means necessary. The resistance of the Water gap between the two elements is very much greater thanlthe total resistancekof the closed circuit. .Inorder that the contact between 8 and 9 is securely maintained afterthe impact of. the lead on the surface .to' be sounded, contact portion .;pin 8 is recessed behind its point. On pressingin thecap, this point .passes the spring 9 and .the latter enters the recess, so thateveniitthe-pressure on the cap ceases, a separation of thecontracts is excluded. r

The safety deviceis represented at 19-.- It consists of .a watertight w capsule of thin sheet metal filled 'with air and provided with .a

detent 20 which is'normally located in a.-

groove 21 on thecontactpin portion 1. Only when the lead has been immersed in water as far as the prescribed depth do the diaphragms of the air-filledcapsule l9 yield-so] that the detent 20is-removed fromithe groove 21, allowing cap and contact pin to,.move against the force ofthe spring 5 towards the 7 inside. lt is sufiicient also to provide the safety capsule with-onlyone diaphragm; M hFi'gure, 2 differs from .Figure 'li merely ,int e I Whereas in Fig. 11 the diaphragm capsule to be controlled by the water pressure carries a, detent pin 20,-.which is .locatedainthepath of movement of the ,pin :4, in Fig. 2 the de-- tentpin is omitted- In place otyit the .elec-,

tricignition circuit passes by way .of conductors .22 23 into the interior of the safety pressure capsule. It terminates in .the .in

construction of the safety device."

terior @of the capsuleein ,two pins 24, 25 sot which fth'e one carries .a .contact spring 26- which islocated abovethe end of tlleotherr The diaphragm 27 is again constructed as manometer diaphragm. On inward movement it presses down the spring 26 and brings it into contact with the counter-contact 25, so that only when the diaphragm 27 has been pressed in, can the ignition circuit be finally completed at contact 9. The inaccessibility of the pressure capsule within the cap 3 practically prevents any unintended pressing in of diaphragm 27.

It is obvious that the particular features of the invention which relate to the safety device and to the form. of the body are applicable not only to electrically operated sounding leads but also to those with any desired signal emission. On the other hand, the use of the electric device, that is to say, the cell and the contact device is, of course, not limited to the particular forms of con.- struction which have the given features of form or safety device. In the same way, any desired compositions of metals and electrolytes of well-known kind or kinds still to be discovered can be arranged in the manner here indicated.

What we claim is 1. A sounding lead comprising in combination a main body; a movable cap at the bottom end of the main body; an electric element adapted to be activated by water; an explosive charge for electrical ignition; a contact mechanism between the cap andthe main body and electric connection lines between the element, the contact mechanism and the explosive charge; and a porous body disposed between the electrodes of said element and carrying an electrolyte in dry form, adapted to be actuated by the water when the device is put into use.

2. A sounding lead comprising in combination a main body; a movable cap at the bottom end of the main body; an electric element adapted to be activated by water; an explosive charge for electrical ignition; a contact mechanism between the cap and the main body and electric connection lines between the element, the contact mechanism and the explosive charge; the electric element containing an electrolyte in dry form between the electrodes and at least one of the electrodes being perforated.

3. A sounding lead comprising in combination a main body built up as a hollow cone of metal; a movable cap at the bottom end of the main body; an electric element one of the electrodes of which is represented by the main body, the other electrode being built up as a concentric cone of other metal within the hollow main body; a layer of fibrous or porous material between the two cones containing electrolytic salt suspended in dry form; an explosive charge for electrical ignition; a contact mechanism between the cap and the main body and electric connection lines hetween the element, the contact mechanism and the explosive charge.

4:. A sounding lead comprising in combination a main body built up as a hollow cone of metal; a movable cap at the bottom end of the main body; an electric element one of the electrodes of which is represented by the main body; the other electrode being built up as a perforated concentric cone of other metal within the hollow main body; a layer of fibrous or porous material between the two cones containing electrolytic salt suspended in dry form; an explosive charge for electrical ignition; a contact mechanism between the cap and the main body and electric connection lines between the element, the contact mechanism and the explosive charge.

5. A sounding lead comprising in combination a main body; a movable cap at the bottom end of the main body; an electric element; an explosive charge for electrical ignition; a contact mechanism in connection with the movable cap and blocked by a detent releasable by the water pressure at a predetermined depth; and electric connection lines between the element, the contact mechanism and the explosive charge; the releasable detent consisting of a watertight closed hollow capsule provided with a flexible diaphragm carrying a pin which normally is inserted in the path of the contact mechanism and removed a on deflection of the diaphragm by the water pressure at a predetermined depth.

6. A sounding lead comprising in combina tion a main body, a movable cap mechanism at the bottom end of themain body, an explosive charge arranged to be detonated by the movement of the movable cap on striking the surface to be sounded, and a releasable lock for normally blocking the movement of said cap, said lock consisting of a water-tight closed hollow capsule provided with a flexible diaphragm carrying a pin which normally is located in the path of said cap mechanism and is removed on deflection of the diaphragm by the water pressure at a desirable depth.

In testimony whereof we aflix our signatures.

WILHELM RUDOLPH. BERNHARD SETTEGAST. 

